Display device, electronic apparatus, and method of manufacturing display device

ABSTRACT

A display device includes an electrode layer and a liquid crystal layer. The electrode layer has a first electrode and a second electrode. The second electrode is opposed to the first electrode and having a plurality of openings extending in a same extending direction. The liquid crystal layer is disposed on the electrode layer. The liquid crystal molecules of the liquid crystal layer in a region in proximity to one side of the opening and liquid crystal molecules of the liquid crystal layer in a region in proximity to another side of the opening, the sides of the opening being opposed to each other in a width direction of the opening, are rotated in opposite directions from each other and aligned.

CROSS REFERENCES TO RELATED APPLICATIONS

This is a Continuation of application Ser. No. 13/655,140, filed on Oct.18, 2012, which claims priority to Japanese Patent Application Number2011-233724, filed on Oct. 25, 2011 and Japanese Patent ApplicationNumber 2012-065248, filed on Mar. 22, 2012, the entire contents of whichare incorporated herein by reference.

BACKGROUND

The present technology relates to a display device controlling liquidcrystal molecules by a transverse electric field, or particularly an FFS(Fringe Field Switching) mode, an electronic apparatus, and a method ofmanufacturing the display device.

Liquid crystal display devices are roughly classified into a verticalelectric field type and a transverse electric field type according tothe direction of an electric field. The transverse electric field typeis more advantageous than the vertical electric field type in that thetransverse electric field type provides a wide viewing angle. Such atransverse electric field type includes an IPS (In-Plane-Switching) modeand the FFS mode (Japanese Patent Laid-Open No. 2008-52161).

In the IPS mode, a pixel electrode and a common electrode are disposedin a same layer, and an electric field mainly occurs in only a directionparallel to a substrate surface. Thus, the electric field is not readilyformed in a region directly above the pixel electrode, and liquidcrystal molecules in the region directly above the pixel electrodecannot be driven. On the other hand, in the FFS mode, a pixel electrodeand a common electrode are superposed on each other with a dielectricfilm interposed between the pixel electrode and the common electrode,and an electric field in an oblique direction with respect to asubstrate surface or an electric field in a radial form occurs, so thatliquid crystal molecules in a region directly above the pixel electrodecan be driven. That is, the FFS mode provides a higher aperture ratiothan the IPS mode.

SUMMARY

However, liquid crystal display devices in such an FFS mode, as withother liquid crystal display devices, have a problem of a slow responsespeed.

The present technology has been made in view of such a problem. It isdesirable to provide a display device having a faster response speed, anelectronic apparatus, and a method of manufacturing the display device.

According to an embodiment of the present technology, there is provideda display device including: an electrode layer including a firstelectrode and a second electrode, the second electrode being opposed tothe first electrode and having a plurality of openings extending in asame extending direction; and a liquid crystal layer disposed on theelectrode layer, liquid crystal molecules of the liquid crystal layer ina region in proximity to one side of the opening and liquid crystalmolecules of the liquid crystal layer in a region in proximity toanother side of the opening, the sides of the opening being opposed toeach other in a width direction of the opening, being rotated inopposite directions from each other and aligned. An electronic apparatusaccording to an embodiment of the present technology includes theabove-described display device.

According to an embodiment of the present technology, there is provideda method of manufacturing a display device. The method includes: formingan electrode layer including a first electrode and a second electrode,the second electrode being opposed to the first electrode and having aplurality of openings extending in a same extending direction; andforming a liquid crystal layer on the electrode layer after performingalignment treatment so that liquid crystal molecules of the liquidcrystal layer in a region in proximity to one side of an opening andliquid crystal molecules of the liquid crystal layer in a region inproximity to another side of the opening, the sides of the opening beingopposed to each other in a width direction of the opening, are rotatedin opposite directions from each other and aligned.

The display device, the electronic apparatus, and the method ofmanufacturing the display device shorten a response time because liquidcrystal molecules in a region in proximity to one side of an opening andliquid crystal molecules in a region in proximity to another side of theopening at a time of application of voltage are rotated in oppositedirections from each other and aligned.

According to the display device, the electronic apparatus, and themethod of manufacturing the display device, liquid crystal molecules ina region in proximity to one side of an opening and liquid crystalmolecules in a region in proximity to another side of the opening arerotated in opposite directions from each other and aligned. Therefore aresponse speed characteristic can be improved. It is thus possible toachieve an increase in response speed in addition to a wide viewingangle and a high aperture ratio realized by driving with a transverseelectric field.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a sectional view of a structure of a display device accordingto a first embodiment;

FIGS. 2A and 2B are plan views of a configuration of a common electrodeshown in FIG. 1;

FIG. 3 is a plan view of an example of modification of corner partsshown in FIGS. 2A and 2B;

FIG. 4 is a plan view of an example of modification of the commonelectrode shown in FIGS. 2A and 2B;

FIGS. 5A and 5B are plan views of the movement of liquid crystalmolecules of a liquid crystal layer shown in FIG. 1;

FIG. 6 is a plan view schematically showing the directions of rotationof the liquid crystal molecules shown in FIGS. 5A and 5B above thecommon electrode;

FIGS. 7A and 7B are plan views showing a configuration of a commonelectrode according to a comparative example;

FIGS. 8A and 8B are plan views showing the movement of liquid crystalmolecules in a case where the common electrode shown in FIGS. 7A and 7Bis used;

FIG. 9 is a diagram showing the response speed of the display deviceshown in FIG. 1;

FIG. 10 is a diagram showing the voltage-luminance characteristic of thedisplay device shown in FIG. 1;

FIGS. 11A and 11B are plan views of a configuration of a commonelectrode according to a modification example 1;

FIG. 12 is a plan view of a configuration of a common electrodeaccording to a modification example 2-1;

FIG. 13 is a plan view of a configuration of a common electrodeaccording to a modification example 2-2;

FIGS. 14A and 14B are sectional views taken along a dotted line A-A′ ofFIG. 2A;

FIG. 15 is a diagram showing an example of a common electrode accordingto a second embodiment;

FIG. 16 is a diagram showing an example of a common electrode accordingto a modification example 3;

FIG. 17 is a diagram showing an example of a common electrode accordingto a modification example 4;

FIG. 18 is a diagram showing an example of a common electrode accordingto a modification example 5-1;

FIG. 19 is a diagram showing an example of a common electrode accordingto a modification example 5-2;

FIG. 20 is a perspective view of an external appearance of a televisiondevice to which the display devices according to the foregoingembodiments and the like are applied;

FIGS. 21A and 21B are perspective views of an external appearance of adigital camera to which the display devices according to the foregoingembodiments and the like are applied;

FIG. 22 is a perspective view of an external appearance of a notebookpersonal computer to which the display devices according to theforegoing embodiments and the like are applied;

FIG. 23 is a perspective view of an external appearance of a videocamera to which the display devices according to the foregoingembodiments and the like are applied; and

FIGS. 24A, 24B, 24C, 24D, 24E, 24F, and 24G are diagrams showing anexternal appearance of a portable telephone to which the display devicesaccording to the foregoing embodiments and the like are applied.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Preferred embodiments of the present technology will hereinafter bedescribed in detail with reference to the drawings.

First Embodiment

FIG. 1 is a sectional view of a structure of a display device accordingto a first embodiment. The display device 1 is a liquid crystal displaydevice of a transverse electric field type. The display device 1includes a backlight 10, a liquid crystal panel 20 in the FFS mode, anda driving circuit (not shown) for driving these parts. Incidentally,FIG. 1 schematically shows the structure of the display device 1, anddoes not necessarily show dimensions and shapes identical to actualdimensions and shapes.

The backlight 10 irradiates the liquid crystal panel 20 from the rear ofthe liquid crystal panel 20. The backlight 10 is for example a surfacelight emitting source of an edge light system. The backlight 10 includesa diffuser and a reflector on the back surface of a light guide plate ofan edge light emitting type. The backlight 10 may be a direct typesurface light emitting source.

The liquid crystal panel 20 generates image light L1 by modulating lightemitted from the backlight 10 according to a video signal, and outputsthe image light L1 from a video display surface 1A. The liquid crystalpanel 20 includes, from the side of the backlight 10, a substrate 21, aTFT (Thin Film Transistor) layer 22, a planarizing layer 23, a pixelelectrode 24 (first electrode), a dielectric film 25, a common electrode26 (second electrode), an alignment film 27 a, a liquid crystal layer28, an alignment film 27 b, and a counter substrate 31. That is, theliquid crystal panel 20 of the transverse electric field type has theliquid crystal layer 28 between the substrate 21 and the countersubstrate 31, and the pixel electrode 24 and the common electrode 26 areboth disposed on the side of the substrate 21. A color filter 32, alight shielding film 33, and an overcoat layer 34 are disposed on thesurface of the counter substrate 31 which surface is opposed to thesubstrate 21. A polarizer 29 a is disposed on the surface of thesubstrate 21 which surface is on the side of the backlight 10. Apolarizer 29 b is disposed on the surface of the counter substrate 31which surface is on the side of the video display surface 1A. Anelectrostatic shielding layer (not shown) may be disposed over thecounter substrate 31 in order to suppress the effects of staticelectricity.

The polarizers 29 a and 29 b are a kind of optical shutter, and passonly light in a certain direction of vibration (polarized light). Thesepolarizers 29 a and 29 b are disposed such that the polarization axes(transmission axes) of the polarizers 29 a and 29 b are displaced fromeach other by 90 degrees. Thereby, the light emitted from the backlight10 passes through the liquid crystal panel 20, or is blocked.

The substrate 21 and the counter substrate 31 are formed by a substratetransparent to visible light, for example a sheet glass or a lighttransmitting resin substrate. The TFT layer 22 has functions ofswitching elements for selecting pixels. The TFT layer 22 is formed byTFTs each including for example a gate electrode, a gate insulatingfilm, a semiconductor film, and a source and a drain electrode. The TFTlayer 22 may be of either of a bottom gate type and a top gate type. Thesemiconductor film may be formed by any of a-Si (amorphous silicon), anoxide semiconductor, an organic semiconductor, and the like. Theplanarizing layer 23 is provided to planarize the surface of the TFTlayer 22 formed on the substrate 21, and has minute connecting holes(not shown) disposed therein to connect the above-described TFTs to thepixel electrode 24. A material providing good pattern accuracy istherefore desirably used as the planarizing layer 23. Such materialsinclude for example organic materials such as polyimide and the like orinorganic materials such as silicon oxide (SiO₂) and the like.

The pixel electrode 24 is provided for each pixel on the planarizinglayer 23. The pixel electrode 24 has for example a rectangular shape,and is regularly arranged in a lattice arrangement, a delta arrangement,or the like. The common electrode 26 is opposed to the pixel electrode24 with the dielectric film 25 between the common electrode 26 and thepixel electrode 24. The dielectric film 25 ensures isolation between thepixel electrode 24 and the common electrode 26, and protects the TFTlayer 22, the pixel electrode 24, and the like. The dielectric film 25is disposed over the entire surface of the substrate 21. The dielectricfilm 25 is formed by a material having a light transmitting property andan insulating property, for example silicon nitride (SiN) or siliconoxide (SiO₂). This dielectric film 25 may also be formed by theplanarizing layer 23, a passivation layer of the TFT layer 22, or thelike.

The common electrode 26 lies astride each pixel, and is disposed in aplanar shape over an entire display region. FIGS. 2A and 2B are planviews of a configuration of the common electrode shown in FIG. 1. Asshown in FIG. 2A, the common electrode 26 has a plurality of rectangularopenings 26A having a length (long side) D and a width (short side) W atsuch positions as to be opposed to the pixel electrode 24. The pluralityof openings 26A are arranged so as to extend in a same extendingdirection (long side direction) (Y-axis direction). In the presentembodiment, liquid crystal molecules of the liquid crystal layer 28 in aregion in proximity to one side of the long sides of an opening 26Awhich long sides are opposed to each other in a direction of width(X-axis direction) and liquid crystal molecules of the liquid crystallayer 28 in a region in proximity to the other side of the long sides ofthe opening 26A at a time of application of voltage are rotated(twisted) in opposite directions from each other (FIG. 5B to bedescribed later) and aligned. This improves a response speedcharacteristic. The length D is for example 10 to 60 μm, and isdesirably less than 40 μm. This is because the direction of rotation(alignment) of the liquid crystal molecules tends to be stabilized whenthe length D is less than 40 μm. The width W is for example 2 to 5 μm. Apitch P in the X-axis direction is 4 to 10 μm. The width W is desirablysmaller for higher response speed.

A plurality of openings 26A arranged in a same row (same position on aY-axis) have upper ends thereof aligned with each other and have lowerends thereof aligned with each other. A plurality of openings 26A inrows adjacent to each other are displaced from each other by ½ P in theX-axis direction, and are arranged in a staggered form. Such a staggeredarrangement brings liquid crystal molecules rotated in a same directionat the openings 26A in the rows adjacent to each other closer to eachother, and thus stabilizes the alignment (FIG. 6 to be described later).The common electrode 26 has a communicating extended-width part 26B formaking openings 26A arranged in the same row communicate with eachother. This communicating extended-width part 26B is formed by couplingregions of the openings 26A adjacent to each other in the X-axisdirection which regions have an extended width in the width directionaround the centers of long sides of the openings 26A. The long sides ofthe openings 26A have four corner parts 26C at points of intersection ofthe long sides of the openings 26A and the communicating extended-widthpart 26B. These corner parts 26C have functions of an electric fieldcontrol section. An electric field control section is to make thedirections of rotation of liquid crystal molecules from one end of anopening 26A in the direction of the long sides of the opening 26A to acorner part 26C identical to each other, and stabilize the directions ofrotation of the liquid crystal molecules. FIG. 3 is a plan view of anexample of modification of the corner parts shown in FIGS. 2A and 2B.FIG. 4 is a plan view of an example of modification of the commonelectrode shown in FIGS. 2A and 2B. As shown in FIG. 3, corner parts 26Cmay be provided without extended-width parts in the form of wedges(extended-width parts 26D) of respective openings 26A communicating witheach other. However, the communicating extended-width parts 26B can bemanufactured more easily than the extended-width parts 26D. In addition,as shown in FIG. 4, the common electrode 26 may be formed withoutextended-width parts (the communicating extended-width parts 26B or theextended-width parts 26D). In this case, the length D is desirablysmall, for example 20 μm or less, in order to stabilize the directionsof rotation. The pixel electrode 24 and the common electrode 26 areformed of a conductive material transparent to visible light, forexample ITO (Indium-Tin-Oxide).

The alignment films 27 a and 27 b are to align the liquid crystalmolecules of the liquid crystal layer 28 in a predetermined direction asdescribed above. The alignment films 27 a and 27 b are formed by forexample a polymeric material such as polyimide or the like that hasundergone a rubbing process. In the display device 1, the alignmentfilms 27 a and 27 b are subjected to a rubbing process for antiparallelalignment in directions parallel to the extending direction of theopenings 26A (FIG. 2B). Thereby, liquid crystal molecules in proximityto one side of an opening 26A and liquid crystal molecules in proximityto the other side of the opening 26A, the sides of the opening 26A beingopposed to each other in a direction of width, at a time of applicationof voltage are rotated in opposite directions from each other andaligned.

Specifically, the alignment film 27 a has been subjected to a rubbingprocess in a rubbing direction D27 a, and the alignment film 27 b hasbeen subjected to a rubbing process in a rubbing direction D27 b, whichis an opposite direction from the rubbing direction D27 a. In addition,the rubbing directions D27 a and D27 b are parallel to the extendingdirection of the openings 26A. A parallel state in this case includes astate in which the rubbing directions D27 a and D27 b intersect theextending direction of the openings 26A at an angle of one degree orless.

The liquid crystal layer 28 is formed by for example a nematic liquidcrystal having negative dielectric anisotropy. The liquid crystal layer28 has a modulating function for transmitting or blocking the incidentlight from the backlight 10 in each pixel according to a voltage appliedfrom the driving circuit. The gradation of each pixel can be adjusted bychanging the level of the light transmission. FIGS. 5A and 5B are planviews of the movement of liquid crystal molecules of the liquid crystallayer shown in FIG. 1. FIG. 5A shows a state of liquid crystal moleculesof the liquid crystal layer 28 above an opening 26A before applicationof a voltage. FIG. 5B shows a state of the liquid crystal molecules ofthe liquid crystal layer 28 above the opening 26A after the applicationof the voltage. The major axes of the liquid crystal molecules beforethe application of the voltage are oriented in substantially a samedirection (Y-axis direction). When the voltage is applied, the liquidcrystal molecules in proximity to one side of the opening 26A and theliquid crystal molecules in proximity to the other side of the opening26A, the sides of the opening 26A being opposed to each other in thewidth direction, are rotated in opposite directions from each other andaligned. Specifically, in the vicinity of one side of the long sides ofthe opening 26A (right side of the page of FIG. 5B), liquid crystalmolecules from an upper end to a corner part 26C are rotated in anR-direction (clockwise) and aligned, and liquid crystal molecules from acorner part 26C to a lower end are rotated in an L-direction(counterclockwise) and aligned. In the vicinity of the other side of thelong sides of the opening 26A (left side of the page of FIG. 5B), liquidcrystal molecules from an upper end to a corner part 26C are rotated inthe L-direction and aligned, and liquid crystal molecules from a cornerpart 26C to a lower end are rotated in the R-direction and aligned.Molecules rotated in the respective directions are mixed with each otherin an intermediate part between the one side and the other side. FIG. 6is a plan view schematically showing the directions of rotation of theliquid crystal molecules shown in FIGS. 5A and 5B above the commonelectrode. FIG. 6 schematically shows the liquid crystal layer 28 withregions rotated in the R-direction as regions 28R and with regionsrotated in the L-direction as regions 28L. As described above, theopenings 26A in rows adjacent to each other are displaced from eachother in the X-axis direction and thereby arranged in a staggered form.Thus, the regions 28L above the openings 26A in the rows adjacent toeach other are close to each other, and the regions 28R above theopenings 26A in the rows adjacent to each other are close to each other,so that the alignment is stabilized. When the liquid crystal layer 28 isa nematic liquid crystal having positive dielectric anisotropy, theliquid crystal molecules can be aligned similarly by subjecting thealignment films 27 a and 27 b to rubbing processes in directions (X-axisdirection) orthogonal to the extending direction of the openings 26A.

The color filter 32 is to effect color separation of the lighttransmitted by the liquid crystal layer 28 into for example the threeprimary colors of red (R), green (G), and blue (B), the four colors ofred, green, blue, and white (W), or the like. The color filter 32 isprovided so as to correspond to the arrangement of the pixel electrode24. This arrangement is for example a stripe arrangement, a diagonalarrangement, a delta arrangement, a rectangle arrangement, or the like.The light shielding film 33 is to reduce crosstalk between the pixels,and has a function of absorbing visible light. The light shielding film33 is a film in the form of a lattice with openings. The openings arearranged in regions opposed to the pixel electrode 24. The overcoatlayer 34 is a coating agent for improving the flatness of the surface ofthe color filter 32, and protecting the surface of the color filter 32.The overcoat layer 34 is formed of an organic material such as a resinor the like or an inorganic material such as SiO₂, SiN, ITO, or thelike.

Such a display device 1 can be manufactured as follows, for example.

First, the TFT layer 22 and the planarizing layer 23 are formed on thesubstrate 21 in this order. Connecting holes for connecting the pixelelectrode 24 to TFTs are made in the planarizing layer 23 byphotolithography techniques. Next, the pixel electrode 24 made of ITOhaving a thickness (thickness in a direction of lamination, whichdirection will hereinafter be referred to simply as a thickness) of 500to 1500 Å, for example, is formed by performing patterning for eachpixel on the planarizing layer 23. Next, the dielectric film 25 made ofsilicon nitride is formed with a thickness of 1000 to 6000 Å on thepixel electrode 24 by a plasma CVD (Chemical Vapor Deposition) method,for example. After the dielectric film 25 is formed, a film of ITO of100 to 1000 Å, for example, is formed by a sputtering method, and thisfilm is etched using a mask. Thereby the common electrode 26 having theopenings 26A and the communicating extended-width parts 26B is formed.The common electrode 26 is thinner than the pixel electrode 24. Thethickness of the common electrode 26 is adjusted in consideration ofresistance and level difference. The alignment film 27 a is formed onthe common electrode 26, and a rubbing process is applied to thealignment film 27 a in a direction parallel to the extending directionof the openings 26A.

Meanwhile, the color filter 32, the light shielding film 33, theovercoat layer 34, and the alignment film 27 b are formed on the side ofthe counter substrate 31 in this order. As with the alignment film 27 a,the alignment film 27 b is subjected to a rubbing process in a directionparallel to the extending direction of the openings 26A. After theformation of up to the alignment film 27 b on the counter substrate 31and the formation of the alignment film 27 a above the substrate 21 asdescribed above, these substrates are opposed to each other, and aliquid crystal is injected into a space between the substrate 21 and thecounter substrate 31, whereby the liquid crystal layer 28 is formed. Theliquid crystal panel 20 is housed in a casing (not shown) together withthe backlight 10 to complete the display device 1.

In the display device 1 according to the present embodiment, when lightin a planar form is emitted from the upper surface of the backlight 10and enters the back surface of the liquid crystal panel 20, pixels areselected, and a predetermined voltage is applied between the pixelelectrode 24 and the common electrode 26. At this time, a transverseelectric field occurs in a region directly above the openings 26A of thecommon electrode 26, and a transverse oblique electric field occurs inother regions, so that the alignment of the liquid crystal molecules ofthe liquid crystal layer 28 is controlled. The incident light from thebacklight 10 passes through the liquid crystal layer 28, so that imagelight L1 is output from the video display surface 1A.

In this case, response speed is increased because liquid crystalmolecules in a region in proximity to one side of the long sides of theopening 26A of the common electrode 26 and liquid crystal molecules in aregion in proximity to the other side of the long sides of the opening26A are rotated in opposite directions from each other and aligned. Thiswill be described in the following using a comparative example.

FIGS. 7A and 7B are plan views showing a configuration of a commonelectrode according to the comparative example. FIGS. 8A and 8B are planviews showing the movement of liquid crystal molecules in a case wherethe common electrode shown in FIGS. 7A and 7B is used. FIG. 7A shows aplanar configuration of the common electrode 126 of a display device(display device 100) according to the comparative example. As with thecommon electrode 26, the common electrode 126 has a plurality ofrectangular openings 126A having a length D100 and a width W100.However, the common electrode 126 does not have communicatingextended-width parts. In the display device 100, as shown in FIG. 7B,alignment films have been subjected to rubbing processes in directionsintersecting the extending direction of the openings 126A at an angle θ,so that all liquid crystal molecules at a time of application of voltageare rotated by the angle θ in a same direction (R-direction) and alignedin order to increase light transmittance (FIG. 8A and FIG. 8B). Thedisplay device 100 therefore has a slow response speed.Double-speed/quadruple-speed driving, a black inserting B/L (backlight),and the like are proposed to improve response speed. However, thesemethods impose a heavy load on a peripheral circuit. Other methods forimproving response speed by OCB (Optically Compensated Bend) (n-cells),a ferroelectric liquid crystal, or a liquid crystal mode such as a bluephase or the like are also proposed. However, these methods also imposea heavy load on a driving circuit, or are difficult to put to practicaluse in terms of reliability or cost.

In the display device 1 according to the present embodiment, on theother hand, liquid crystal molecules in proximity to one side of thelong sides of an opening 26A and liquid crystal molecules in proximityto the other side of the long sides of the opening 26A are rotated inopposite directions from each other and aligned (FIG. 5B), so that theresponse speed is improved. FIG. 9 is a diagram showing the responsespeed of the display device shown in FIG. 1. FIG. 9 shows results ofmeasurement of response speeds Ton and Toff of the display device 1 andthe display device 100. Solid lines represent the response speed of thedisplay device 1. Broken lines represent the response speed of thedisplay device 100. At the time of the measurement, the widths W andW100 of the openings 26A and 126A were 3 μm, and the pitches P and P100of the openings 26A and 126A were 6 μm. Thus, the response speeds weremeasured under similar conditions except for the rubbing directions ofthe alignment films. As a result, the response speed Ton of the displaydevice 100 was 27 ms, and the response speed Toff of the display device100 was 25 ms, whereas the response speed Ton of the display device 1was 10.75 ms, and the response speed Toff of the display device 1 was6.5 ms. Thus, it can be confirmed that the response speed of the displaydevice 1 is improved. In particular, the display device 1 can improvethe response speed Toff, which cannot be supplemented by overdriving,and the response speed Toff of the display device 1 is increased fourtimes or more as compared with the display device 100. In addition, aliquid crystal material and a driving method used in a liquid crystaldisplay device in the past can be used as they are. The display device 1can therefore be readily put to practical use.

It is considered that the response speed of such a display device 1 isincreased due to a higher voltage applied in the display device 1. FIG.10 is a diagram showing the voltage-luminance characteristic of thedisplay device shown in FIG. 1. FIG. 10 shows relation between theapplied voltage and brightness (luminance) of the display device 1 andthe display device 100. A solid line represents the voltage-luminancecharacteristic of the display device 1. A broken line represents thevoltage-luminance characteristic of the display device 100. FIG. 10shows that the applied voltage of the display device 1 is higher thanthe applied voltage of the display device 100 when compared at the samebrightness. This is because liquid crystal molecules rotated in oppositedirections from each other are mixed with each other in a region aroundthe middle of one side and the other side of the long sides of anopening 26A. This improves the response speed of the display device 1.

As described above, in the present embodiment, liquid crystal moleculesin a region in proximity to one side of the long sides of an opening 26Aof the common electrode 26 and liquid crystal molecules in a region inproximity to the other side of the long sides of the opening 26A arerotated in opposite directions from each other and aligned. Thereforethe response speed can be improved. In addition, driving in thetransverse electric field type can widen a viewing angle and improve anaperture ratio.

Further, because the common electrode 26 has the communicatingextended-width parts 26B, the corner parts 26C can be provided to theopenings 26A. A corner part 26C makes the direction of rotation ofliquid crystal molecules from one end (the upper end or the lower end)of the opening 26A to the corner part 26C the same direction, andstabilizes the direction of alignment of the liquid crystal molecules.

Examples of modification of the present technology will be described inthe following. Constituent elements common to those of the foregoingembodiment are identified by the same reference numerals, anddescription thereof will be omitted.

Modification Example 1

FIGS. 11A and 11B are plan views of a configuration of a commonelectrode according to a modification example 1. As shown in FIG. 11A,the common electrode 46 is different from the common electrode 26 in theforegoing embodiment in that the upper sides and lower sides of openings46A are displaced from each other in a direction of width (X-axisdirection) and arranged in a staggered form with communicatingextended-width parts 46B interposed between the upper sides and thelower sides of the openings 46A. Incidentally, the long sides of theopening 46A have four corner parts 46C at points of intersection of thelong sides of the opening 46A and the communicating extended-width parts46B.

In the common electrode 46, one opening 46A is separated into an upperside and a lower side (in the Y-axis direction) with a communicatingextended-width part 46B interposed between the upper side and the lowerside, and the upper side and the lower side of the opening 46A Aredisposed so as to be displaced from each other by ½ P in the widthdirection. Openings 46A in a same row are therefore arranged in astaggered form. When one opening 46A is thus disposed so as to bedisplaced in the width direction, regions 48L in which liquid crystalmolecules are rotated in the L-direction are aligned with each other andregions 48R in which liquid crystal molecules are rotated in theR-direction are aligned with each other in the extending direction ofthe openings 46A (Y-axis direction), as shown in FIG. 11B. Therefore thealignment of the liquid crystal molecules is more stabilized than in theforegoing embodiment.

Modification Example 2-1

FIG. 12 is a plan view of a configuration of a common electrodeaccording to a modification example 2-1. The common electrode 56 isdifferent from the common electrode 26 in the foregoing embodiment inthat the common electrode 56 has openings 56A in substantially a rhombicshape. Incidentally, the long sides of an opening 56A have four cornerparts 56C at points of intersection of the long sides of the opening 56Aand a communicating extended-width part 56B.

The openings 56A are in substantially a rhombic shape formed by cuttingoff two corners on an upper side and a lower side. The sides in theextending direction (Y-axis direction) of the openings 56A are inclinedat a predetermined angle to the Y-axis. Thereby, even when thedirections of rubbing of alignment films somewhat deviate from theY-axis direction due to a manufacturing error, the deviation istolerated by the inclination, so that liquid crystal molecules can bealigned stably.

Modification Example 2-2

FIG. 13 is a plan view of a configuration of a common electrodeaccording to a modification example 2-2. As shown in FIG. 13, the commonelectrode 56′ is different from the common electrode 26 in the foregoingembodiment in that the common electrode 56′ has openings 56′A insubstantially a rhombic shape and in that the upper sides and lowersides of the openings 56′A are displaced from each other in a directionof width (X-axis direction) and arranged in a staggered form withcommunicating extended-width parts 56′B interposed between the uppersides and lower sides of the openings 56′A. Incidentally, the long sidesof an opening 56′A have four corner parts 56′C at points of intersectionof the long sides of the opening 56′A and the communicatingextended-width parts 56′B.

The openings 56′A are in substantially a rhombic shape formed by cuttingoff two corners on an upper side and a lower side. The sides in theextending direction (Y-axis direction) of the openings 56′A are inclinedat a predetermined angle to the Y-axis. Thereby, even when thedirections of rubbing of alignment films somewhat deviate from theY-axis direction due to a manufacturing error, the deviation istolerated by the inclination, so that liquid crystal molecules can bealigned stably.

In the common electrode 56′, one opening 56′A is separated into an upperside and a lower side (in the Y-axis direction) with a communicatingextended-width part 56′B interposed between the upper side and the lowerside, and the upper side and the lower side of the opening 56′A aredisposed so as to be displaced from each other by ½ P in the widthdirection. Openings 56′A in a same row are therefore arranged in astaggered form. When one opening 56′A is thus disposed so as to bedisplaced in the width direction, regions in which liquid crystalmolecules are rotated in the L-direction are aligned with each other andregions in which liquid crystal molecules are rotated in the R-directionare aligned with each other in the extending direction of the openings56′A (Y-axis direction). Therefore the alignment of the liquid crystalmolecules is more stabilized than in the foregoing embodiment.

Second Embodiment

Description will next be made of a second embodiment.

In the display device 1 according to the first embodiment, the rubbingdirection D27 a of the alignment film 27 a on the side of the substrate21 is parallel to the extending direction of the openings 26A providedin the common electrode 26. Thus, a rising direction of the liquidcrystal molecules of the liquid crystal layer 28 in the vicinity of theopenings 26A may be unstable.

FIGS. 14A and 14B are sectional views taken along a dotted line A-A′ ofFIG. 2A. FIG. 14A shows a state in which no electric field is suppliedto the liquid crystal layer 28. FIG. 14B shows a state in which anelectric field is supplied to the liquid crystal layer 28.

As shown in FIG. 14A, when no electric field is supplied to the liquidcrystal layer 28, all the liquid crystal molecules 28 a are present in astate of being rotated in a rotation direction R1 by a predeterminedangle to a horizontal direction such that ends of the liquid crystalmolecules 28 a in the rubbing direction D27 a are situated above ends ofthe liquid crystal molecules 28 a in the opposite direction. Therotation direction R1 of the liquid crystal molecules 28 a at this timeis referred to also as a pretilt direction.

When an electric field is supplied to the liquid crystal layer 28 inthis state, as shown in FIG. 14B, the liquid crystal molecules 28 arise. In this case, the liquid crystal molecules 28 a situated in aregion extending in the rubbing direction D27 a from a position wherethe opening 26A intersects the communicating extended-width part 26Brise so as to be rotated in the same direction as the pretilt direction(rotation direction R1). On the other hand, the liquid crystal molecules28 a situated in a region extending in an opposite direction from therubbing direction D27 a from the position where the opening 26Aintersects the communicating extended-width part 26B rise so as to berotated in an opposite direction (rotation direction R2) from thepretilt direction.

Incidentally, this phenomenon can occur also in the cases of the commonelectrode 26 shown in FIG. 3, the common electrode 46 shown in FIG. 11A,the common electrode 56 shown in FIG. 12, and the common electrode 56′shown in FIG. 13.

Thus, in the display device 1, the direction of alignment of the liquidcrystal layer 28 in the vicinity of the openings 26A may not be stable.

On the other hand, a display device according to the second embodimentcan stabilize the direction of alignment of the liquid crystal layer 28.

FIG. 15 is a diagram showing an example of a common electrode accordingto the second embodiment.

The display device according to the second embodiment has a commonelectrode 66 with openings in a different shape from those of the commonelectrode 26 in the display device 1 according to the first embodiment.Incidentally, the other configuration of the display device according tothe second embodiment is similar to that of the display device 1.

As with the common electrode 26 shown in FIG. 2A, the common electrode66 has a plurality of openings 66A extending in a Y-axis direction andcommunicating extended-width parts 66B extending in an X-axis directionand intersecting the openings 66A.

In this case, the openings 66A intersect the communicatingextended-width parts 66B at a position closer to end parts 66 b in anopposite direction from the rubbing direction D27 a than end parts 66 ain the rubbing direction D27 a. That is, when the openings 66A aredivided into openings 66AA including the end parts 66 a and openings66AB including the end parts 66 b with the position of intersection withthe communicating extended-width parts 66B as a boundary in theextending direction (Y-axis direction), the length D2 of the openings66AB is shorter than the length D1 of the openings 66AA. Incidentally,the length D2 can be set to “0.”

According to this configuration, the ratio of the liquid crystalmolecules 28 a rising so as to be rotated in the opposite direction fromthe pretilt direction when an electric field is supplied can be reducedin the liquid crystal layer 28, and thus the direction of alignment ofthe liquid crystal layer 28 can be stabilized.

Modification Example 3

An example of modification of the common electrode of the display deviceaccording to the second embodiment will next be described as amodification example 3.

FIG. 16 is a diagram showing an example of a common electrode accordingto the modification example 3.

As with the common electrode 26 shown in FIG. 3, the common electrode 76has a plurality of openings 76A extending in a Y-axis direction andprovided with extended-width parts 76D.

In this case, the extended-width parts 76D are disposed at a positioncloser to end parts 76 b in an opposite direction from a rubbingdirection D27 a than end parts 76 a in the rubbing direction D27 a inthe openings 76A. That is, when the openings 76A are divided intoopenings 76AA including the end parts 76 a and openings 76AB includingthe end parts 76 b with the position of intersection with theextended-width parts 76D as a boundary in the extending direction(Y-axis direction), the length D4 of the openings 76AB is shorter thanthe length D3 of the openings 76AA. Incidentally, the length D4 can beset to “0.”

According to this configuration, the ratio of the liquid crystalmolecules 28 a rising so as to be rotated in the opposite direction fromthe pretilt direction when an electric field is supplied can be reducedin the liquid crystal layer 28, and thus the direction of alignment ofthe liquid crystal layer 28 can be stabilized.

Modification Example 4

Another example of modification of the common electrode of the displaydevice according to the second embodiment will next be described as amodification example 4.

FIG. 17 is a diagram showing an example of a common electrode accordingto the modification example 4.

As with the common electrode 46 shown in FIG. 11A, the common electrode86 has a plurality of openings 86A extending in a Y-axis direction andcommunicating extended-width parts 86B extending in an X-axis directionand intersecting the openings 86A. Further, one side and another side ofthe openings 86A, which sides are divided from each other in theextending direction (Y-axis direction) with the communicatingextended-width parts 86B as a boundary between the sides, are disposedso as to be displaced from each other in the width direction (X-axisdirection).

In this case, the openings 86A intersect the communicatingextended-width parts 86B at a position closer to end parts 86 b in anopposite direction from a rubbing direction D27 a than end parts 86 a inthe rubbing direction D27 a. That is, when the openings 86A are dividedinto openings 86AA including the end parts 86 a and openings 86ABincluding the end parts 86 b with the position of intersection with thecommunicating extended-width parts 86B as a boundary in the extendingdirection (Y-axis direction), the length D6 of the openings 86AB isshorter than the length D5 of the openings 86AA. Incidentally, thelength D6 can be set to “0.”

According to this configuration, the ratio of the liquid crystalmolecules 28 a rising so as to be rotated in the opposite direction fromthe pretilt direction when an electric field is supplied can be reducedin the liquid crystal layer 28, and thus the direction of alignment ofthe liquid crystal layer 28 can be stabilized.

Modification Example 5-1

Yet another example of modification of the common electrode of thedisplay device according to the second embodiment will next be describedas a modification example 5-1.

FIG. 18 is a diagram showing an example of a common electrode accordingto the modification example 5-1.

As with the common electrode 56 shown in FIG. 12, the common electrode96 has a plurality of openings 96A in substantially a rhombic shapewhich openings 96A extend in a Y-axis direction and communicatingextended-width parts 96B extending in an X-axis direction andintersecting the openings 96A.

In this case, the openings 96A intersect the communicatingextended-width parts 96B at a position closer to end parts 96 b in anopposite direction from a rubbing direction D27 a than end parts 96 a inthe rubbing direction D27 a. That is, when the openings 96A are dividedinto openings 96AA including the end parts 96 a and openings 96ABincluding the end parts 96 b with the position of intersection with thecommunicating extended-width parts 96B as a boundary in the extendingdirection (Y-axis direction), the length D8 of the openings 96AB isshorter than the length D7 of the openings 96AA. Incidentally, thelength D8 can be set to “0.”

According to this configuration, the ratio of the liquid crystalmolecules 28 a rising so as to be rotated in the opposite direction fromthe pretilt direction when an electric field is supplied can be reducedin the liquid crystal layer 28, and thus the direction of alignment ofthe liquid crystal layer 28 can be stabilized.

Modification Example 5-2

Yet another example of modification of the common electrode of thedisplay device according to the second embodiment will next be describedas a modification example 5-2.

FIG. 19 is a diagram showing an example of a common electrode accordingto the modification example 5-2.

As with the common electrode 56′ shown in FIG. 13, the common electrode96′ has a plurality of openings 96′A in substantially a rhombic shapewhich openings 96′A extend in a Y-axis direction and communicatingextended-width parts 96′B extending in an X-axis direction andintersecting the openings 96′A. Further, one side and another side ofthe openings 96′A, which sides are divided from each other in theextending direction (Y-axis direction) with the communicatingextended-width parts 96′B as a boundary between the sides, are disposedso as to be displaced from each other in the width direction (X-axisdirection).

In this case, the openings 96′A intersect the communicatingextended-width parts 96′B at a position closer to end parts 96′b in anopposite direction from a rubbing direction D27 a than end parts 96′a inthe rubbing direction D27 a. That is, when the openings 96′A are dividedinto openings 96′AA including the end parts 96′a and openings 96′ABincluding the end parts 96′b with the position of intersection with thecommunicating extended-width parts 96′B as a boundary in the extendingdirection (Y-axis direction), the length D10 of the openings 96′AB isshorter than the length D9 of the openings 96′AA. Incidentally, thelength D10 can be set to “0.”

According to this configuration, the ratio of the liquid crystalmolecules 28 a rising so as to be rotated in the opposite direction fromthe pretilt direction when an electric field is supplied can be reducedin the liquid crystal layer 28, and thus the direction of alignment ofthe liquid crystal layer 28 can be stabilized.

Examples of Application

Description will next be made of examples of application of the displaydevices described in the foregoing embodiments and the foregoingmodification examples. The display devices according to the foregoingembodiments and the like are applicable as display devices of electronicapparatuses in all fields which electronic apparatuses display anexternally input video signal or a video signal generated within theelectronic apparatuses as an image or video, such as television devices,digital cameras, notebook personal computers, portable terminal devicessuch as portable telephones and the like, video cameras, or the like.

First Example of Application

FIG. 20 is a perspective view of an external appearance of a televisiondevice to which the display devices according to the foregoingembodiments and the like are applied. This television device has forexample a video display screen section 300 including a front panel 310and a filter glass 320. The video display screen section 300 is formedby one of the display devices according to the foregoing embodiments andthe like.

Second Example of Application

FIGS. 21A and 21B are perspective views of an external appearance of adigital camera to which the display devices according to the foregoingembodiments and the like are applied. FIG. 21A is a perspective view ofthe external appearance as viewed from a front side. FIG. 21B is aperspective view of the external appearance as viewed from a back side.This digital camera has for example a light emitting section 410 forflashlight, a display section 420, a menu switch 430, and a shutterbutton 440. The display section 420 is formed by one of the displaydevices according to the foregoing embodiments and the like.

Third Example of Application

FIG. 22 is a perspective view of an external appearance of a notebookpersonal computer to which the display devices according to theforegoing embodiments and the like are applied. This notebook personalcomputer has for example a main unit 510, a keyboard 520 for operationsof inputting characters and the like, and a display section 530 fordisplaying an image. The display section 530 is formed by one of thedisplay devices according to the foregoing embodiments and the like.

Fourth Example of Application

FIG. 23 is a perspective view of an external appearance of a videocamera to which the display devices according to the foregoingembodiments and the like are applied. This video camera has for examplea main body section 610, a lens 620 for taking a subject, which lens isdisposed in a front side surface of the main body section 610, astart/stop switch 630 at a time of picture taking, and a display section640. The display section 640 is formed by one of the display devicesaccording to the foregoing embodiments and the like.

Fifth Example of Application

FIGS. 24A to 24G are diagrams showing an external appearance of aportable telephone to which the display devices according to theforegoing embodiments and the like are applied. FIG. 24A is a front viewof the portable telephone in an opened state. FIG. 24B is a side view ofthe portable telephone in the opened state. FIG. 24C is a front view ofthe portable telephone in a closed state. FIG. 24D is a left side viewof the portable telephone in the closed state. FIG. 24E is a right sideview of the portable telephone in the closed state. FIG. 24F is a topview of the portable telephone in the closed state. FIG. 24G is a bottomview of the portable telephone in the closed state. This portabletelephone is for example formed by coupling an upper side casing 710 anda lower side casing 720 to each other by a coupling part (hinge part)730. The portable telephone has a display 740, a sub-display 750, apicture light 760, and a camera 770. The display 740 or the sub-display750 is formed by one of the display devices according to the foregoingembodiments and the like.

The present technology has been described above by citing embodimentsand examples of modification. However, the present technology is notlimited to the foregoing embodiments and the like, but is susceptible ofvarious modifications. For example, in the foregoing embodiments and thelike, description has been made of a case where an electric fieldcontrol section is provided by the extended-width parts (communicatingextended-width parts). However, the electric field control section maybe formed by distributing films of different dielectric constants on thecommon electrode.

In addition, a case where openings are provided on the side of thecommon electrode has been illustrated in the foregoing embodiments andthe like. However, openings may be provided on the side of the pixelelectrode in place of the openings on the side of the common electrode.

Further, for example, the materials and thicknesses or the formingmethods and forming conditions or the like of the respective partsdescribed in the foregoing embodiments and the like are not limited, butmay be other materials and thicknesses or other forming methods andforming conditions.

It is to be noted that the present technology can also adopt thefollowing constitutions.

(1) A display device including:

an electrode layer including a first electrode and a second electrode,the second electrode being opposed to the first electrode and having aplurality of openings extending in a same extending direction; and

a liquid crystal layer disposed on the electrode layer, liquid crystalmolecules of the liquid crystal layer in a region in proximity to oneside of the opening and liquid crystal molecules of the liquid crystallayer in a region in proximity to another side of the opening, the sidesof the opening being opposed to each other in a width direction of theopening, being rotated in opposite directions from each other andaligned.

(2) The display device according to the above (1),

wherein the openings have an electric field control section, and liquidcrystal molecules from an end of the opening to the electric fieldcontrol section in the extending direction are rotated in a samerotation direction.

(3) The display device according to the above (2),

wherein the openings have an extended-width part in the width directionof the openings, and the electric field control section is a corner partdisposed at a point of intersection of the opening and theextended-width part.

(4) The display device according to the above (3),

wherein the extended-width part is a communicating extended-width partfor making the openings adjacent to each other in the width directioncommunicate with each other.

(5) The display device according to the above (4),

wherein an upper side part and a lower side part of the opening aredisplaced from each other in the width direction and arranged in astaggered form with the communicating extended-width part interposedbetween the upper side part and the lower side part of the opening.

(6) The display device according to one of the above (1) to (5),

wherein an alignment film is disposed between the electrode layer andthe liquid crystal layer, and the alignment film has been subjected to arubbing process in a direction parallel to the extending direction.

(7) The display device according to the above (1),

wherein an alignment film is disposed between the electrode layer andthe liquid crystal layer, the alignment film having been subjected to arubbing process in a predetermined direction parallel to the extendingdirection, and

the openings have an extended-width part at a position closer to an endpart in a direction opposite from the predetermined direction than anend part in the predetermined direction.

(8) The display device according to the above (7),

wherein the extended-width part is a communicating extended-width partfor making the openings adjacent to each other in the width directioncommunicate with each other.

(9) The display device according to the above (8),

wherein the openings are divided into a first opening and a secondopening in the extending direction with the communicating extended-widthpart as a boundary, and the first opening and the second opening aredisposed so as to be displaced from each other in the width direction.

(10) The display device according to one of the above (1) to (9),

wherein the openings adjacent to each other in the extending directionare displaced from each other in the width direction and arranged in astaggered form.

(11) The display device according to one of the above (1) to (10),

wherein the openings have a rectangular shape.

(12) The display device according to one of the above (1) to (10),

wherein the openings have a substantially rhombic shape.

(13) The display device according to one of the above (1) to (12),

wherein a dielectric film is disposed between the first electrode andthe second electrode.

(14) An electronic apparatus including:

a display device;

wherein the display device includes

-   -   an electrode layer including a first electrode and a second        electrode, the second electrode being opposed to the first        electrode and having a plurality of openings extending in a same        extending direction, and    -   a liquid crystal layer disposed on the electrode layer, liquid        crystal molecules of the liquid crystal layer in a region in        proximity to one side of the opening and liquid crystal        molecules of the liquid crystal layer in a region in proximity        to another side of the opening, the sides of the opening being        opposed to each other in a width direction of the opening, being        rotated in opposite directions from each other and aligned.

(15) A method of manufacturing a display device, the method including:

forming an electrode layer including a first electrode and a secondelectrode, the second electrode being opposed to the first electrode andhaving a plurality of openings extending in a same extending direction;and

forming a liquid crystal layer on the electrode layer after performingalignment treatment so that liquid crystal molecules of the liquidcrystal layer in a region in proximity to one side of an opening andliquid crystal molecules of the liquid crystal layer in a region inproximity to another side of the opening, the sides of the opening beingopposed to each other in a width direction of the opening, are rotatedin opposite directions from each other and aligned.

1. A display device comprising: an electrode layer including: a firstelectrode; and a second electrode, wherein the second electrode isopposed to the first electrode and has a plurality of openings, each ofthe openings has a width extending in a width direction and a lengthextending in an extending direction, the length is greater than thewidth, respective ones of the openings each have a first side and asecond side that are opposed to each other in the width direction, theopenings have a communication part in the width direction, and thecommunicating part communicates the openings adjacent to each other inthe width direction; a liquid crystal layer that includes liquid crystalmolecules, and that is disposed on the electrode layer; and an alignmentfilm that is disposed between the electrode layer and the liquid crystallayer, wherein, in a perspective from a thickness direction of theliquid crystal layer, respective ones of the liquid crystal molecules ina first region in proximity to the first side of the opening andrespective ones of the liquid crystal molecules in a second region inproximity to the second side are rotated in opposite directions fromeach other and aligned, wherein the alignment film aligns the liquidcrystal molecules of the liquid crystal layer in a predetermineddirection when a voltage is not applied to the liquid crystal layer,wherein the predetermined direction is parallel to the extendingdirection, wherein the openings adjacent to each other in the extendingdirection are displaced from each other in the width direction andarranged in a staggered form, and wherein regions in which the liquidcrystal molecules are rotated in a same direction are aligned in theextending direction with each other.
 2. The display device according toclaim 1, wherein the openings have an electric field control section,and the liquid crystal molecules from an end of the opening to theelectric field control section in the extending direction are rotated ina same rotation direction.
 3. The display device according to claim 2,wherein the electric field control section is a corner part disposed ata point of intersection of the opening and the communicating part. 4.The display device according to claim 1, wherein an upper side part anda lower side part of the opening are displaced from each other in thewidth direction and arranged in a staggered form with the communicatingpart interposed between the upper side part and the lower side part ofthe opening.
 5. The display device according to claim 1, wherein thecommunicating part is arranged at a position closer to an end part in adirection opposite from the predetermined direction parallel to theextending direction than an end part in the predetermined direction. 6.The display device according to claim 1, wherein the openings aredivided into a first opening and a second opening in the extendingdirection with the communicating part as a boundary, and the firstopening and the second opening are disposed so as to be displaced fromeach other in the width direction.
 7. The display device according toclaim 1, wherein the openings have a rectangular shape.
 8. The displaydevice according to claim 1, wherein the openings have a substantiallyrhombic shape.
 9. The display device according to claim 1, wherein adielectric film is disposed between the first electrode and the secondelectrode.